does it has to be support very old versions of clojure

https://github.com/metosin/ring-swagger/blob/master/project.clj#L23

I can refactor some of my code (update-vals ) instead of (for [[k v] lot of time if clojure version is latest

I'm not sure, I usually err on the side of supporting older versions. could you refactor it at least to use reduce-kv or transducers?

or backport update-vals

okay I will do that

I still think we should support 1.11 onwards but I'll leave it to you